Anchor system for an invert form



March 23, 1965 c. I. wILLIAMs ANCHOR SYSTEM FOR AN INVERT FORM 2 Sheets-Sheet 1 Filed April 15, 1963 CHESTER l WILLIAMS INVENTOR.

March 23, 1965 c. I. WILLIAMS 3,174,204

ANCHOR SYSTEM FOR AN INVERT FORM Filed April 15, 1963 V 2 Sheets$heet 2 MIIIIIIIIII FIG. 3 FIG. 4

FIG. 5

FIG. 6

I l l\ 29/ 24 26 25 24 FIG. 7

\ CHESTER I. WILLIAMS I INVENTOR.

BY 5 WM United States Patent 3,174,204 ANCHOR SYSTEM FOR AN INVERT FORM Chester 1. Williams, 347 Greenbriar SE,

1 Grand Rapids, Mich. Filed Apr. 15, 1963, Ser. No. 273,152

Claims. (Cl. 25-1315) This invention relates to the securing of forms for placing poured concrete, and has been developed in conjunction with the problems encountered in lining a tunnel. The curvature of the funnel walls in cross section presents a problem in accurately establishing the inside surface and positioning the usual reinforcing rods without interfering with the pouring operation. This work is done through the use of forms which extend over sectors, or portions of the cross section of the tunnel. These extend axially" along the tunnel for a distance representing a convenient pour. The central portion of the bottom of the tunnel is often referred to as an invert, and the form system used in producing it is essentially a pair of side rails with suitable cross beam structure, the rails being used (a) to establish a clean side boundary for the pour at the inside surface, and (b) to provide guide shelves for a screed which can be moved along these rails to establish the surface of the concrete.

Prior techniques for securing the rail and beam assembly have included temporary stakes positioned outside the rails, or adjustable projections secured to the ends of the transverse beams for engagement with the sidewalls of the rock formation outside of the area between the rails where the concrete is placed. This type of arrangement is obviously somewhat insecure, but has been resorted to in view of the undesirability of using more adequate structure which had to be left in the concrete after the form has served its purpose. This invention provides for securing the invert form with much greater solidity than the usual make-shift devices, and has the distinct advantage of establishing anchoring points which can be used later (after the invert pour has set) to secure the heavy form structure used to position the concrete for the other portions of the cross section of the tunnel. All this is accomplished with the use of a very small amount of equipment which has to be left in place after the pour has been completed. The several features of the invention will be analyzed in detail through a discussion of the particular embodiments illustrated in the accompanying drawings. In the drawings:

FIGURE 1 is a sectional elevation showing a portion of the invert section of a tunnel in a rock formation, with the concrete in position as determined by the associated form structure. 7

FIGURE 2 is an enlarged sectional view of the Structure associated with the anchoring system.

' FIGURE 3 is a side elevation, partially in section, and on an enlarged scale, showing the cone nut appearing in FIGURES l and 2.

FIGURE 4 is an end view of the device shown in FIGURE 3.

FIGURE 5 is a plan view of the extension arm connecting the anchor with the form rail.

FIGURE 6 is an elevation of the arm shown in FIG- URE 5.

FIGURE 7 is a perspective view of the wedge used to temporarily lock the extension arm to the form rail.

Referring to the drawings, the structure provided by this invention is associated with the application of a concrete lining indicated at 10 to form a tunnel wall in the rock formation 11. The central portion of this concrete lining at the bottom of the tunnel is referred to as the invert, and will normally exhibit considerable curvature in cross section. A form structure for positioning this concrete is indicated generally at 12, and includes a pair of parallel side rails 13, only one of these being shown on the drawings. These rails are interconnected by suitable cross beams 14, and the details of tms portion of the structure form no part of this invention.

The rail 13 is oifset at 15 to provide the shelf 16, which functions as a guide rail for a screed, not shown. The screed is a standard device which is used to determine the exposed inside surface 17 of the concrete. The shelves 16 function as guideways along which the screed may be dragged so that all of the freshly-poured concrete above the surface 17 is scraped along ahead of the screed. This practice is conventional, and the present invention is centered primarily in the arrangement for holding the structure associated with the rails 13 firmly in position so that the forces involved in the operation of the screed can be adequately resisted.

The angle 18 is secured to the lower flange 19 of the rail 13, and the leg 2 of the angle 18 is perforated at a series of points along its length to accommodate the tongueszl of the arms 22, These arms are shown in FIGURES 5 and 6, and are pieces of angular cross sec tion in which the lower flange 23 is terminated short of the end to provide the tongue 21. When the tongue 21 has been inserted in the appropriate aperture in the flange 20, the Wedge 24 is inserted in the hole 25 in the tongue 21, and driven into place.' The result of this operation is to entrap the flange 20 between the wedge 24 and the spaced abutments provided by the end 26 of theflange 23 and the end 27 of the lanced portion 28.

At the opposite end of the arm 22, a hole 29 receives the end of the anchor rod 30, which engages the hole 31 drilled in the adjacent rock formation. Normally, the anchor 30 will be grouted in place with a cementitious composition; and on hardening of this material, the anchor '30 becomes a solid reference point to which the entire structure can be secured. The anchor 30 can be of a variety of conventional designs, and is normally provided with standard threading 32 atits outer end. A nut 33 engages this threading, and forms an abutment against which the arm 22 may rest. A tapped hole 29 may be used in place of the nut 33 if desired. The connection is completed by the application .of the elongated cone nut 34, which is shown in detail in FIGURES'3 and 4. The periphery of the nut 34 is slightly conical in configuration, with the lower end 35 bearing against the flange 23 of the arm 22'. The cone nut 34 is threaded throughout a major portion of its length, and terminates in a major diameter at the upper end 36, which is preferably provided with a hexagonal recess 37 for receiving a wrench. The length of the cone nut 34 is selected so that it extends into close proximity with the surface 17 of the concrete (which is to be determined by the interaction of a screed with the shelves 16). It is preferable-to include a cap 42 in the assembly which can be slipped over the end 36 of the cone nut in order to prevent the ingress of concrete into the recess 37 and the internal thread system. As an alternative, a plug can be inserted in the recess 37, rather than covering the entire end of the cone nut.

\ The adjustment of the rods with respect to the arms can be roughly determined, and the entire assembly then supported by suitable temporary members during the insertion of the grout in the holes 31, which finally determines the position of the anchor rods 30. For this purpose, the stakes 38 can serve as a temporary support, being withdrawn after they have accomplished their function. The extensible end 39 can also be used to engage the rough wall of the rock formation to provide a temporary positioning device for the assembly associated with the beams 14. It may also be noted that the form assembly, in addition to positioning the surface 17, will also normally be used to locate the reinforcing rods 49 and 41 with respect to the surface 17. This is conventional practice, and forms no part of the invention. After the grout has set around the anchor rods 30, the nuts 33 and 34 can be more carefully adjusted to accurately place the form. The concrete is then poured.

After the concrete has hardened, the cap 42 may be removed from the. end of the cone nut 34. This can either be done through jamming a pointed object through the end of the frangeable' material of which the cap is preferably made, or the cap may be provided with a peripheral lip or flange at its upper end under which a screw driver or some equivalent instrument may be inserted to lift the cap out of the concrete. When the end of the cone nut has been thus exposed, a wrench inserted in the recess 37 can be applied to unscrew the cone nut from the end of the anchor rod 30. A conical recess formed in the concrete by the cone nut 34 is now available as a socket for receiving a heavy so-called she-bolt of conventional design for securing the forms that position the concrete around the remainder of the wall of the tunnel. The form assembly 12 can be disconnected from the anchor system by the removal of the wedges 24, which frees the rails 13 for disengagement from the tongues 21. The connection between the rails 13 and the transverse beams 14 must be loosened in order to provide for this movement, but this presents no particular problem. The arms 22 and the anchor rods 30 (and possibly the nuts 33) are the only portions of the structure which remain embedded in the concrete as the form is moved on to a succeeding position.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. An anchor assembly for positioning a form struc ture, said anchor assembly comprising:

an anchor rod for engagement with cast concrete, and

having a threaded outer end;

an inner nut engaging the threaded end of said anchor rod;

an arm engaging said anchor rod outwardly from said inner nut and extending laterally therefrom;

a form structure including a supporting rail;

locking means for disengageably locking said arm to said rail, said locking means being accessible on the side of said rail opposite from said arm;

an elongated nut securing said arm to said anchor rod, said nut extending coaxially with said anchor rod to a point adjacent the position of surface of the concrete determined by said form structure to provide access to said threaded end for connection thereto; and

removable cap means for covering the end of said nut and excluding concrete therefrom.

2. An anchor assembly for positioning a form structure, said anchor assembly comprising:

an anchor rod for engagement with cast concrete, and

having a threaded outer end;

an arm engaging said anchor rod and extending laterally therefrom, said anchor rod being initially suspended from said arm;

a form structure including a supporting rail, said rail extending opposite the end of said arm; locking means for disengageably locking said arm to said rail, said locking means being accessible on the side of said rail opposite from said arm;

removable means extending from and coaxially with said anchor rod to a point adjacent the position of surface of the concrete determined by said form structure to provide access to said anchor rod for connection thereto, 1

tit

3. An anchor assembly for positioning a form structure, said anchor assembly comprising:

an anchor rod disposed substantially vertically for engagement With cast concrete, said anchor rod having a threaded upper end;

an arm engaging said anchor rod and extending laterally therefrom, said arm having a projection extending from a shoulder at the end of said arm opposite from said anchor rod;

'a form structure including a substantially horizontal supporting rail, said rail extending opposite the end of said arm and having an opening receiving said projection;

locking means for disengageably locking said arm to said rail, said locking means being accessible on the side of said rail opposite from said arm;

an elongated nut securing said arm to said anchor rod, said nut extending coaxially with said anchor rod to a point adjacent the position of surface of the concrete determined by said form structure to provide access to said anchor rod for connection thereto; and

removable cap means for covering the end of said nut and excluding concrete therefrom.

4. An anchor assembly for positioning a form structure, said anchor assembly comprising:

an anchor rod for engagement with cast concrete;

an arm engaging said anchor rod and extending lateral-.

ly therefrom, said arm having a projection extending from a shoulder at the end of said arm opposite from said anchor rod;

a form structure including a supporting rail, said rail extending opposite the end of said arm and having an opening receiving said projection;

locking means for disengageably locking said arm to said rail, said locking means being accessible on the side of said rail opposite from said arm; and

an elongated nut securing said arm to said anchor rod, said nut extending substantially beyond said arm coaxially with said anchor rod to a point adjacent the surface of the concrete determined by said form structure to provide access to said anchor rod for connection thereto.

5. An anchor assembly for positioning a form structure, said anchor assembly comprising:

an anchor rod for engagement with cast concrete;

an arm secured to said anchor rod and extending laterally therefrom;

a form structure including a supporting rail, said rail extending opposite the end of said arm;

locking means for disengageably locking said arm to said rail, said locking means being accessible on the side of said rail opposite from said arm; and

removable means extending from and coaxially with said anchor rod to a point adjacent the position of surface of the concrete determined by said form structure to provide access to said anchor rod for connection thereto.

References Cited in the file of this patent UNITED STATES PATENTS 1,175,011 Phillipofi Mar. 14, 1916 1,924,560 Leriche et al Aug. 29, 1933 1,956,046 Robertson Apr. 24, 1934 1,976,595 Asleson et. a1 Oct. 9, 1934 2,270,286 Gerriets J an. 20, 1942 2,902,742 Matich Sept. 8, 1959 2,976,596 Williams Mar. 28, 1961 FOREIGN PATENTS 516,010 Great Britain Dec. 20, 1939 812,289 Great Britain Apr. 22, 1959 108,249 Pakistan Sept. 24, 1958 

1. AN ANCHOR ASSEMBLY FOR POSITIONING A FORM STRUCTURE, SAID ANCHOR ASSEMBLY COMPRISING: AN ANCHOR ROD FOR ENGAGEMENT WITH CAST CONCRETE, AND HAVING A THREADED OUTER END; AN INNER NUT ENGAGING THE THREADED END OF SAID ANCHOR ROD; AN ARM ENGAGING SAID ANCHOR ROD OUTWARDLY FROM SAID INNER NUT AND EXTENDING LATERALLY THEREFROM; A FORM STRUCTURE INCLUDING A SUPPORTING RAIL; LOCKING MEANS FOR DISENGAGEABLY LOCKING SAID ARM TO SAID RAIL, SAID LOCKING MEANS BEING ACCESSIBLE ON THE SIDE OF SAID RAIL OPPOSITE FROM SAID ARM; AN ELONGATED NUT SECURING SAID ARM TO SAID ANCHOR ROD, SAID NUT EXTENDING COAXIALLY WITH SAID ANCHOR ROD TO A POINT ADJACENT THE POSITON OF SURFACE OF THE CONCRETE DETERMINED BY SAID FROM STRUCTURE TO PROVIDE ACCESS TO SAID THREADED END FOR CONNECTION THERETO; AND REMOVABLE CUP MEANS COVERING THE END OF SAID NUT AND EXCLUDING CONCRETE THEREFROM. 